Thanks, Bart. Yes I've done that but on the latest version of CC, Adobe has 'moved' the plugin folders to a centralised 'Application Support' Library folder , separate from the Photoshop subdirectories (at least on Mac OS X) and this is adding difficulties to Affinity plugin compatibility.
Graham, above, kindly posted a link to Affinity plug-in support (thank you, Graham) but I can tell you that that list doesn't reflect my experience. Both Topaz Clarity & Detail, to name but two, don't work consistently - so much so that, IMO, it's not worth the trouble - yet.
It's a good, very good app, but the reality, I suspect, is that we've been become too ingrained into the Photoshop 'way' over the years , which is still the industry standard, and my guess is it'll remain so - not least because of extensive plug-in usage and macro programming. Affinity is a great program as a 'Layers for C1 / Lr', and easy to incorporate into a workflow as long as one keeps it simple. Interesting Haze Removal filter and good implementation of both Frequency Separation and Liquify too - though Liquify is nowhere near as accomplished as the latest Adobe version.
A more extensive plug-in compatibility program would go a long way to improving its usefulness as a Ps replacement, though I can see it's a more attractive proposition to users of CS6, less so to users of CC.